Provided by: libcurl4-doc_7.81.0-1ubuntu1.19_all bug

NAME

       CURLOPT_DOH_URL - provide the DNS-over-HTTPS URL

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DOH_URL, char *URL);

DESCRIPTION

       Pass  in  a  pointer  to a URL for the DoH server to use for name resolving. The parameter
       should be a char * to a null-terminated string which must be URL-encoded in the  following
       format: "https://host:port/path". It MUST specify a HTTPS URL.

       libcurl  does  not  validate the syntax or use this variable until the transfer is issued.
       Even if you set a crazy value here, curl_easy_setopt(3) will still return CURLE_OK.

       curl sends POST requests to the given DNS-over-HTTPS URL.

       To find the DoH server itself, which might be specified using a name, libcurl will use the
       default  name lookup function. You can bootstrap that by providing the address for the DoH
       server with CURLOPT_RESOLVE(3).

       Disable DoH use again by setting this option to NULL.

INHERIT OPTIONS

       DoH lookups use SSL  and  some  SSL  settings  from  your  transfer  are  inherited,  like
       CURLOPT_SSL_CTX_FUNCTION(3).

       The  hostname  and  peer  certificate  verification  settings are not inherited but can be
       controlled separately via CURLOPT_DOH_SSL_VERIFYHOST(3) and CURLOPT_DOH_SSL_VERIFYPEER(3).

       A set CURLOPT_OPENSOCKETFUNCTION(3) callback is not inherited.

DEFAULT

       NULL - there is no default DoH URL. If this option  is  not  set,  libcurl  will  use  the
       default name resolver.

PROTOCOLS

       All

EXAMPLE

       CURL *curl = curl_easy_init();
       if(curl) {
         curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
         curl_easy_setopt(curl, CURLOPT_DOH_URL, "https://dns.example.com");
         curl_easy_perform(curl);
       }

AVAILABILITY

       Added in 7.62.0

RETURN VALUE

       Returns CURLE_OK on success or CURLE_OUT_OF_MEMORY if there was insufficient heap space.

       Note  that curl_easy_setopt(3) will not actually parse the given string so given a bad DoH
       URL, curl will not detect a problem until it tries to resolve a name with it.

SEE ALSO

       CURLOPT_VERBOSE(3), CURLOPT_RESOLVE(3),